Studies have been performed to establish the utility of the rhesus cytomegalovirus (CMV) model for studying key questions regarding congenital transmission of cmv. Four fetuses were experimentally infected intraperitoneal with rhesus CMV (RHCMV) via ultrasound-guidance on gestational day (gd) 60 (early second trimester). The inoculum contained either the 68-1 strain of rhcmv, first isolated in 1968, strain 21252, isolated from healthy monkeys at the crprc, or a combination of both. Fetuses were monitored sonographically each week post-inoculation until necropsy on gd 130 (third trimester). Four of 4 fetuses showed widespread dissemination of rhcmv dna, as detected by pcr, at the time of necropsy. Infected tissues included liver, spleen, thymus, lymph nodes, and brain. Two fetuses had severe degenerative changes of brain parenchyma with multiple patches of calcification; lissencephaly, polymicrogyria, ventriculomegaly, and leptomeningitis were also observed. Both fetuses exhibited significant patches of calcification in the liver, and one fetus was growth-restricted. All 4 fetuses had elevated lymphocyte counts at the time of necropsy. Investigations with the cmv-infected fetal monkey model will provide essential information on the biology of rhcmv which will be particularly relevant for studies on the viral mechanisms of congenital transmission and pathogenesis, host immune response to congenital infection, and vaccine strategies to prevent or limit cmv infection in the human.